.banner {
    margin-top: 5rem;
    width: 100%;
    height: 38rem;
    position: relative;
}
.banner ul {
    width: 100%;
    height: 100%;
}
.banner ul li {
    width: 100%;
    height: 100%;
    display: none;
    background-size: cover !important;
}
.banner ul li:nth-child(1) {
    background: url(../image/banner1.jpg
    ) center top no-repeat;
}
.banner ul li:nth-child(2) {
    background: url(../image/banner2.jpg) center top no-repeat;
}
.banner ul li:nth-child(3) {
    background: url(../image/banner3.jpg) center top no-repeat;
}
.banner .banner-img {
    display: block;
}
.banner ol {
    width: 90px;
    height: 30px;
    position: absolute;
    left: 50%;
    bottom: 10px;
    transform: translate(-50%,0);
}
.banner ol li {
    float: left;
    width: 20px;
    height: 20px;
    background-color: #fff;
    margin-right: 10px;
}
.banner .banner-icon {
    border: 2px solid #12dbff;
}
.banner .banner-left,
.banner .banner-right {
    position: absolute;
    top: 50%;
    transform: translate(0,-50%);
    width: 5rem;
    height: 5rem;
    font-size: 3rem;
    text-align: center;
    line-height: 5rem;
    color: rgba(255, 255, 255, .5);
    cursor: pointer;
    border-radius: 3px;
}
.banner .banner-left:hover,
.banner .banner-right:hover {
    color: #fff;
    background-color: rgba(18, 219, 255, .5);
}
.banner-left {
    left: 20px;
}
.banner-right {
    right: 20px;
}